@jaraco, is there anything that prevents it from being merged?

Tests?

And why do you need that? Why not run python setup.py egg_info in the setuptools directory first?

Will try that, though it likely won't work. We need bdist_wheel workable to install setuptools properly (setup.py install doesn't set needed entry points), so I ended-up with the following dockerfile: https://gitlab.com/KOLANICH-subgroups/docker-images/fixed_python/raw/master/Dockerfile

Tests?

I feel like the only proper way to test it is to run the part of the mentioned Dockerfile in a clean environment.

(closed/reopened to trigger GH events/CI stuff)

Will try that, though it likely won't work.

Any updates?

In fact no, I haven't added any tests.

I'm closing this (without prejudice). Feel free to comment and we can re-open. Or re-submit when ready. Thanks.

There will be no tests and likely no reopening, since it seems it is not needed by the project. If it was, it'd have been already implemented and this PR wouldn't have been existing at all.
It feels like everyone except me is OK with depending on prebuilt packages from pip. For me it is simpler to modify my CI pipelines so the sources of setuptools are patched, than to implement tests making no sense (that stuff should be "tested" every time setuptools package is built) in order to meet formal requirements for accepting of the patch into upstream. So be it.

The question I'd like to see answered is this one:

And why do you need that? Why not run python setup.py egg_info in the setuptools directory first?

If you add that between steps 3 and 4, does that work?

@benoit-pierre, @jaraco, thank you. It works for GitLab CI pipeline: https://gitlab.com/KOLANICH-subgroups/docker-images/fixed_python/-/jobs/1648667066

But not for GitHub Actions one: https://github.com/KOLANICH-libs/RichConsole.py/runs/3797498484

AttributeError: type object 'Distribution' has no attribute '_finalize_feature_opts'

echo "##[group] Bootstrapping packaging";
	git clone --depth=50 https://github.com/pypa/setuptools.git;
	git clone --depth=50 https://github.com/pypa/pip.git;
	git clone --depth=50 https://github.com/pypa/wheel.git;
	cd ./setuptools;
	python3 ./setup.py egg_info;

	cd ../wheel;
	python3 -c "import re;from pathlib import Path;f=Path('setup.cfg');f.write_text(re.subn('^setup_requires.+$', '', f.read_text(), flags=re.MULTILINE)[0])";
	PYTHONPATH=../setuptools:./src sudo python3 ./setup.py install;
	cd ../;

	cd ./setuptools;
	python3 ./setup.py bdist_wheel;
	PYTHONPATH=../pip/src sudo python3 -m pip install --upgrade --pre ./dist/*.whl;

(I hope that I have correctly guessed what you mean under between steps 3 and 4)

The traceback in that run is thus:

Traceback (most recent call last):
    File "./setup.py", line 87, in <module>
      dist = setuptools.setup(**setup_params)
    File "/home/runner/work/RichConsole.py/RichConsole.py/setuptools/setuptools/__init__.py", line 153, in setup
      return distutils.core.setup(**attrs)
    File "/usr/lib/python3.8/distutils/core.py", line 108, in setup
      _setup_distribution = dist = klass(attrs)
    File "/home/runner/work/RichConsole.py/RichConsole.py/setuptools/setuptools/dist.py", line 453, in __init__
      _Distribution.__init__(
    File "/usr/lib/python3.8/distutils/dist.py", line 292, in __init__
      self.finalize_options()
    File "/home/runner/work/RichConsole.py/RichConsole.py/setuptools/setuptools/dist.py", line 830, in finalize_options
      for ep in sorted(loaded, key=by_order):
    File "/home/runner/work/RichConsole.py/RichConsole.py/setuptools/setuptools/dist.py", line 829, in <lambda>
      loaded = map(lambda e: e.load(), filtered)
    File "/home/runner/work/RichConsole.py/RichConsole.py/setuptools/pkg_resources/__init__.py", line 2450, in load
      return self.resolve()
    File "/home/runner/work/RichConsole.py/RichConsole.py/setuptools/pkg_resources/__init__.py", line 2460, in resolve
      raise ImportError(str(exc)) from exc
  ImportError: type object 'Distribution' has no attribute '_finalize_feature_opts'

You'll notice that _finalize_feature_opts is an old entry point, probably present due to an existing installation of setuptools. Se here's what I think is happening:

1. An old version of Setuptools with that entrypoint is still present.
2. When setuptools.dist.Distribution.finalize_options is called, it enumerates all of the setuptools.finalize_distribution_options entry points and calls each.
3. Because the old setuptools declares a setuptools.dist.Distribution._finalize_feature_opts as one of those entry points, Setuptools attempts to load it.
4. The local copy of setuptools is newer and doesn't have that entry point.
5. Because the local setuptools Python package is ahead on the Python path, an error occurs trying to load that entry point.

You have a few options here. You could manually uninstall setuptools from the system site packages. Or you could try running with -S to avoid the implied import site to exclude system site packages. Or you could get a CI image that includes a newer version of Setuptools without that metadata.

Regardless, I don't think adding entry points to the bootstrapping metadata would help here.

I recommend to file a new issue to track the missed expectation if there still is one.

Yeah, I have already solved this issue by

sudo rm -rf /usr/lib/python3/dist-packages/setuptools;
sudo rm -rf /usr/lib/python3/dist-packages/setuptools-*.egg-info;

Thanks anyway.